August 22, NASA completed a set of maneuvers on the Tropical Rainfall
Measuring Mission (TRMM) spacecraft to boost its orbit around Earth. The
push into a higher orbit will prolong the satellite’s life and continue
to provide meteorologists and climatologists data to forecast and better
understand global climate change.

satellite was gently nudged to its new orbit altitude under the control
of NASA engineers at Goddard Space Flight Center in Maryland. Now after
the satellite’s successful first three years, and with fuel starting to
run low, scientists realized that they could extend the mission’s life
and gather further vital information by raising TRMM’s orbit from 350
kilometers (km) to 402 km away from Earth.

TRMM satellite has been recording rainfall data over the tropics since
it was launched in 1997. TRMM has already achieved or surpassed many of
its original goals since it became operational. These include collecting
data on rainfall and the heat release associated with rainfall, as well
as information about interactions between water vapor, clouds and precipitation
that are central to regulating the climate system.

TRMM’s orbit to 402 km could extend the lifespan of TRMM to somewhere
between 2005 and 2007," said TRMM Project Scientist, Dr. Robert Adler
of NASA Goddard.

changing the orbit, NASA engineers do not have to burn as much fuel to
make orbit adjustments to counter effects of drag and friction at 350
km. More importantly, from a science standpoint, an extended mission provides
a more robust climate record of rainfall. It also gives scientists a chance
to capture additional information about the global
changes in rainfall that occur during El Nino and La Nina events. "The
extension of TRMM’s life also creates an opportunity to verify data with
future missions, like NASA’s AQUA (a water cycle mission satellite that
includes rainfall measurements) and Japan’s ADEOS II (The Advanced Earth
Observing Satellite II)," continues Dr. Adler.

extended mission would benefit operational weather forecasters, scientists
addressing critical questions related to climate change and global warming,
and policymakers," said Goddard Research Meteorologist, Dr. J. Marshall

the pressing need to understand climate change better and faster, a longer
record of TRMM data can be combined with data being collected from the
current satellites like Terra, and future climate monitoring satellites
like AQUA and ADEOS II. The wide variety of data sources will provide
more complete parameters to feed into NASA global climate models. This
in turn could lead to further improvements in climate prediction. And,
a longer TRMM mission also allows scientist to more firmly establish potential
links between pollution and rainfall suppression.

centers like the NOAA’s National Hurricane Center and the Department of
Defense’s Joint Typhoon Warning Center can continue to use TRMM data for
hurricane identification and monitoring. Additionally, NOAA’s National
Center for Environmental Prediction and the European Center for Medium
Range Weather Forecasting (ECMWF) are just now beginning to test TRMM
data in weather forecasts models, such that an extension of TRMM mission
life has potential future benefits in weather prediction.

is a joint mission between NASA and the Japanese Space Agency (NASDA).

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more information on the TRMM mission, visit http://trmm.gsfc.nasa.gov.

For more information about AQUA, see: http://eos-pm.gsfc.nasa.gov/

For more information about ADOES-II see: